I started with a code for the Jace, Arcane Strategist planeswalker deck. And I've looked at upgrade paths, and then started making adjustments from there, with mixed results. I feel my curve is out of shape, but I struggle in discerning which cards are the problem/unnecessary in my curve. I've lost perspective I feel, and could use a deckbuilder's insight.

Deck: {U}{G}

Sideboard:

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Main combos inclued Zegana into Bioessence Hydra, at 4 mana, I can tap 4 lands and retap one by untapping with Zegana to play Hydra ahead of curve by one turn, to summon a 10/10 trample that can snowball hard with any proliferate effects. Furthermore Zegana can untap Hydra to give it pseudo vigilance.

Rabid Bite is for some direct removal if they have threats I can't weasel through.

Sharktocrab is great for competing with other midrange decks, and it allows me to slow down some aggro, depending on how tall/wide their board is.

I had Bethnic Biomancer for a threat that can help me cycle out my higher cost cards so I can play on curve, but I found myself feeling too bad about discarding cards that all work together, with little graveyard synergy.

My sideboard I must admit, is terrible, because I don't know how to sideboard very well, so I kinda gave up on it and just put in techs for whichever deck has enchantments or annoying flying creatures.

I've noticed a lot that I struggle to deal with Vampire of the Dire Moon, which is really annoying because it can easily take out my huge Hydra, but Rabid Bite is overkill and a waste of my resources.

If I fall behind, I tend to have little to no hope of recuperating my board to compete.

I'd love some critique and some guidance to where I may be going in the wrong direction. This is my first deck that I've played/invested in in MTG:A so I appreciate any basics that I may not be aware of.

Thank you.